The Four Cs

Diamonds are judged on several factors that determine their beauty. Most diamonds never reach the consumer market because they are too flawed. Often, these diamonds are used for industrial purposes -- as an abrasive, for drill bits or for cutting diamonds and other gems. If you've ever purchased a diamond, you've heard of the "4 Cs:"

1. Cut - This refers to a diamond's geometric proportions and how it has been cut. When a diamond is cut, facets are created and the diamond's finished shape is determined.
2. Clarity - This is the measurement of a diamond's flaws, or inclusions that are seen in the diamond. Clarity levels begin with Flawless and move down to Very Very Slight (VVS), Very Slight (VS) and Slightly Included (SI).
3. Carat - This is the weight of a diamond. One carat is equal to about 200 milligrams.
4. Color - In referring to transparent diamonds, the color scale runs from D to Z, beginning with Icy White -- the color of the most expensive transparent diamonds -- and ending with a light yellow.